im having a hard time finding this card, any card that I find from colorful with 1GB of memory have 256 Bit bus not 128.
According to Gforce.com the 9800gt never came in ddr2 format, you would have to drop down to the 9500 gt where they made a Gddr3 and DDR2 card. Even GPUreview shows that they only made a Gddr3 card not a DDR2